A microprocessor based semi-automatic data collection and correction unit has been built to measure both pH shifts and heats of reactions using a dual differential measurement cell which contains fast thermistors, fast pH electrodes, and is temperature stabilized. The data is collected with a 16 bit A/D converter and is displayed and plotted in real time. The data is then stored on disk, a separate program corrects the data for heat losses using finite element techniques. During data collection, the processor controls a syringe drive to deliver the reactants.